These 2 flags can be used only for dual-stack clusters. For non dual-stack clusters, continue to use  `--node-cidr-mask-size` flag to configure the mask size.

    The default node cidr mask size for IPv6 was 24 which is now changed to 64. ([#79993](https://github.com/kubernetes/kubernetes/pull/79993), [@aramase](https://github.com/aramase))